The present invention relates to a ski boot and, more particular, to a fastening device which is used in a ski boot to fasten and hold a foot within an outer shell of the ski boot.
Generally, a conventional ski boot includes a front entry system boot into which a foot is inserted from the front side of the boot, and a rear entry system boot into which a foot is inserted from the rear side thereof. As disclosed in Japanese Patent Publications No. 2-249501 of Heisei and No. 2-154701 of Heisei, in either of the front and rear entry systems, fastening and holding of the foot within the outer shell of the boot after the foot is inserted is currently performed by a fastening device which utilizes the dead point action of a clamping lever with respect to a shaft support point.
However, the clamping action of the clamping lever is sometimes released by shocks given when a skier wearing such ski boots skies in a bumpy slope, which provides a trouble in skiing to the skier and even puts the skier into a dangerous condition. In order to improve this, there is disclosed in Japanese Utility Model Publication No. 63-68803 of Showa a fastening device in which the holding force of a clamping lever is increased by use of a magnet. However, even the improved clamping lever is not able to accomplish its object, that is, it is not able to provide sufficient holding force to bear against the shocks given in skiing, and also corrosion unfavorably occurs. Further, the clamping lever using the dead point action requires a greater force than necessary for its opening and closing operation, especially, for an opening operation, which results in a poor operationability. The present invention aims at eliminating the drawbacks found in the prior art devices and it is an object of the invention to provide a fastening device for use in a ski boot which is able to surely fasten and hold a fastening lever.